Two small tools for musicians and producers: tap along to a beat to find its BPM (tempo) without a metronome, or look up the exact frequency in Hz and MIDI note number for any musical note across the audible range, from a low C0 up to the highest notes on a standard piano keyboard.
Both calculators run instantly in your browser with no installation, plugin or account required. Tap tempo is handy for setting a DAW's project tempo by ear from a reference track, while the note frequency tool helps with instrument tuning, synthesizer programming and everyday music theory practice.